Electrode and nonaqueous electrolyte battery

Patent metadata

Field	Value
Publication number	US-2016308202-A1
Application number	US-201615196732-A
Country	US
Kind code	A1
Filing date	Jun 29, 2016
Priority date	Jan 6, 2014
Publication date	Oct 20, 2016
Grant date	—

Abstract

According to one embodiment, an electrode is provided. The electrode includes an electrode mixture layer and a current collector. The electrode mixture layer contains active material particles. The electrode mixture layer includes a first surface being in contact with the current collector and a second surface separated from the first surface by a thickness of the electrode mixture layer. The electrode mixture layer includes a first portion having the first surface and a second portion having the second surface. In the first portion, a first oxide layer is formed on the active material particle. In the second portion, a second oxide layer is formed on the active material particles. The thickness of the first oxide layer is more than the thickness of the second oxide layer.

First claim

What is claimed is:

1 . An electrode comprising:
an electrode mixture layer comprising active material particles comprising Li and at least one transition metal selected from the group consisting of Fe, Mn, Co and Ni; and a current collector comprising at least one surface on which the electrode mixture layer is supported, wherein: the electrode mixture layer comprises a first surface being in contact with the current collector and a second surface separated by a thickness of the electrode mixture layer from the first surface; the electrode mixture layer comprises: a first portion having a thickness of at least 20% of the thickness of the electrode mixture layer and comprising the first surface; and a second portion having a thickness of at least 20% of the thickness of the electrode mixture layer and comprising the second surface; in the first portion of the electrode mixture layer, a first oxide layer is formed on surfaces of the active material particles, the first oxide layer comprising at least one element selected from the group consisting of Li, Mg, Ca, B, Al, Si, P, Fe, Mn, Co, Ni, Cu, Zn, Zr, Nb, Mo, Ta, and W, and having a thickness of more than 0.5 nm and 100 nm or less; in the second portion of the electrode mixture layer, a second oxide layer is formed on surfaces of the active material particles, the second oxide layer comprising at least one element selected from the group consisting of Li, Mg, Ca, B, Al, Si, P, Fe, Mn, Co, Ni, Cu, Zn, Zr, Nb, Mo, Ta, and W, and having a thickness of 0.5 nm or more and less than 100 nm; and the thickness of the first oxide layer is more than the thickness of the second oxide layer.

2 . The electrode according to claim 1 , wherein a ratio of the thickness of the first oxide layer to the thickness of the second oxide layer is 5 or more.

3 . The electrode according to claim 1 , wherein a ratio of the thickness of the first oxide layer to the thickness of the second oxide layer is 200 or less.

4 . The electrode according to claim 1 , wherein a ratio of the thickness of the first oxide layer to the thickness of the second oxide layer is 5 or more and 50 or less.

5 . The electrode according to claim 1 , wherein the active material particles comprises at least one selected from the group consisting of a lithium-manganese composite oxide, a lithium-nickel composite oxide, a lithium-cobalt composite oxide, a lithium-nickel-cobalt composite oxide, a lithium-manganese-cobalt composite oxide, lithium-iron phosphate and a lithium composite phosphate compound.

6 . The electrode according to claim 1 , wherein the first oxide layer comprises at least one selected from the group consisting of NiO, CoO, MnO, MgO, CaO, AlPO 4 , Fe 3 O 4 , CuO, ZnO, Li 4 P 2 O 7 , ZrO 2 , Nb 2 O 5 , MoO 3 , Ta 2 O 5 , WO 3 , SiO 2 , Al 2 O 3 , and Li 2 O-2B 2 O 3 .

7 . The electrode according to claim 1 , wherein the first oxide layer comprises at least one selected from the group consisting of NiO, CoO, MnO, MgO, CaO, AlPO 4 , Fe 3 O 4 , CuO, ZnO, Li 4 P 2 O 7 , ZrO 2 , Nb 2 O 5 , MoO 3 , Ta 2 O 5 , WO 3 , SiO 2 , Al 2 O 3 , and Li 2 O-2B 2 O 3 .

8 . The electrode according to claim 1 , wherein
the first oxide layer comprises a first compound comprising the at least one element selected from the group consisting of Li, Mg, Ca, B, Al, Si, P, Fe, Mn, Co, Ni, Cu, Zn, Zr, Nb, Mo, Ta, and W; the second oxide layer comprises a second compound comprising the at least one element selected from the group consisting of Li, Mg, Ca, B, Al, Si, P, Fe, Mn, Co, Ni, Cu, Zn, Zr, Nb, Mo, Ta, and W; and the first compound is identical to the second compound.

9 . A nonaqueous electrolyte battery comprising:
the electrode according to claim 1 as a positive electrode; a negative electrode; and a nonaqueous electrolyte.

10 . The nonaqueous electrolyte battery according to claim 9 , wherein the negative electrode comprises a negative electrode active material of which a lithium insertion-and-extraction potential is higher than a redox potential of lithium by a value of 1 V or more.

11 . The nonaqueous electrolyte battery according to claim 10 , wherein the negative electrode active material comprises lithium titanate having a spinel structure.

Assignees

• Toshiba Kk

Inventors

• Kuriyama Hiromichi
• Saruwatari Hidesato
• Satake Hideki

Classifications

• H01M4/485

  of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy (H01M4/505, H01M4/525 take precedence) · CPC title

• H01M4/131

  Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M4/366 Primary

  as layered products · CPC title

• H01M4/525

  of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy · CPC title